In the field of telecommunications, numerous customers are connected with the switch of a telecommunications company over telecommunications lines. Such customers can also sometimes be referred to as subscribers. The switch is often called an exchange or “PBX” (central office exchange operated by the telecommunications company). Between the subscriber and the switch, sections of the telecommunications lines are connected with telecommunications modules. Telecommunications modules establish an electrical connection between one wire attached to the telecommunications module at a first side and another wire attached to the telecommunications module at a second side. The wires of one side can also be called incoming wires and the wires of the other side can be called outgoing wires. Plural telecommunications modules can be put together at a distribution point such as a main distribution frame (or “MDF”), an intermediate distribution frame, an outside cabinet or at some other distribution point located, for example, in an office building or on a particular floor of an office building. At such distribution points, racks can be provided on which carriers are directly mounted, allowing plural telecommunications modules to be directly attached to the carriers. To allow flexibility in wiring some telecommunications lines are connected with a set of first telecommunications modules in a manner to constitute a permanent connection. Flexibility is realized by jumpers or cross-connects, which flexibly connect contacts of the first telecommunications modules with contacts of a set of second telecommunications modules. These jumpers can be changed, for example, when a person moves within an office building to a new telephone (i.e., a different telephone line) and he or she wants to keep a former telephone number. Such a change of jumpers can be called patching or cross-connecting. Within the telecommunications module disconnection points can be located in the electrical connection between the two sides. Disconnection plugs can be inserted at the disconnection points to disconnect the line. Protection plugs and magazines are also sometimes used. They are connected to the module and protect any equipment connected to the wires from overcurrent and overvoltage. Test plugs can also be inserted at a disconnection point to test or monitor a line.
Recently, Asymmetric Digital Subscriber Line, or “ADSL” technology has spread widely in the field of telecommunications. ADSL technology allows at least two different signals to be transmitted on a single line and is achieved by transmitting the different signals at different frequencies along the line. Signals are combined at a particular point in the telecommunications line and split at another point. In particular, at the subscriber side separate voice and data signals are combined and sent to the central office over one line. In the central office the combined signal is split. The voice signal is then directed to the other subscriber(s) on the telephone call, and the data signal is directed to the other subscriber(s) participating in the data exchange. For transmission of voice and data signals to the subscriber, separate voice and data signals are combined at the central office, sent to the subscriber and split at the subscriber side. After splitting the POTS, or “plain old telephone service” can be used to transmit voice signals. The remaining portion of the split signal can be used to transmit data or other information. Splitters, which are used to split or combine the signal, can generally be arranged at any distribution point.
Any electronic components necessary to perform the above functions can be contained, sometimes together with a printed circuit board as a base, in a single splitter module. Other functional modules include protection modules, which contain components to provide protection against overvoltage and/or overcurrent, and testing and monitoring modules, which contain suitable electronic components to test and/or monitor a telecommunications line. Other functional modules or plugs are also known.